We establish some results characterizing central or axial symmetry of convex sets in the hyperbolic plane. The characterizations follow the spirit of a Chakerian-Klamkin's characterization of central symmetry for Euclidean sets: if for any three point-subset M of a compact set K there is a symmetric image of M that is also contained in K, then K has a center of hyperbolic symmetry. We also study axial symmetry when the axis is either a geodesic, a horocycle, or a hypercycle. Finally, in the last section we give a characterization of the hyperbolic disc.

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Jesús Jerónimo-Castro

Facultad de Ingenieria, Universidad Autónoma de Querétaro, Querétaro, México

jesusjero@hotmail.com

Francisco G. Jimenez-Lopez

Facultad de Ingenieria, Universidad Autónoma de Querétaro, Querétaro, México

fjimenez@uaq.mx
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J. Jerónimo-Castro, F. G. Jimenez-Lopez. “Symmetries of Convex Sets in the Hyperbolic Plane.” Journal of Convex Analysis 26 (2019), No. 4, 1077–1088. https://doi.org/10.68381/jca26059